Results of peak-flow frequency analysis for selected streamgages in or near Montana, based on data through water year 2015 (ver. 1.1, August 2020)

The USGS Wyoming-Montana Water Science Center (WY–MT WSC) recently completed a report documenting methods for peak-flow frequency analysis following implementation of the Bulletin 17C guidelines. The methods are used to provide estimates of peak-flow quantiles for 50-, 42.9-, 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent annual exceedance probabilities (AEPs) for selected streamgages operated by the WY–MT WSC. In association with the report, this data release presents peak-flow frequency analyses for 99 selected streamgages that serve as examples showing various aspects of the WY-MT WSC frequency-analysis methods.